Microbial fuel cells (MFCs) that generate electricity generation from a broad diversity of biomass and organic substrates through microbial metabolism have attracted considerable research interest as an alternative clean energy technology and energy‐efficient wastewater treatment method. Despite encouraging successes and auspicious pilot‐scale experiments of the MFCs, increasing doubts about their viability for practical large‐scale applications are being raised. Low performance, expensive core parts and materials, energy‐intensive operation, and scaling bottlenecks question a sustainable development. Instead, special MFCs for low‐power battery‐reliant devices might be more applicable and potentially realizable. Such bacteria‐powered biobatteries would enable i) a truly stand‐alone device platform suitable for use in resource‐limited and remote regions, ii) simple, on‐demand power generation within a programmed period of time, and iii) a tracelessly biodegradable battery due to the use of the bacteria used for power generation. The biobattery would be an excellent power solution for small‐scale, on‐demand, single‐use, and disposable electronics. Recent progress of small‐scale MFC‐based biobatteries is critically reviewed with specific attention toward various device platforms. Furthermore, comments and outlook related to the potential directions and challenges of the biobatteries are discussed to offer inspiration to the community and induce fruitful future research.
Bacteria‐powered biobatteries using multiple microbial species under well‐mixed conditions demonstrate a temporary performance enhancement through their cooperative interaction, where one species produces a resource that another species needs but cannot synthesize. Despite excitement about the artificial microbial consortium, those mixed populations cannot be robust to environmental changes and have difficulty generating long‐lasting power because individual species compete with their neighbors for space and resources. In nature, microbial communities are organized spatially as multiple species are separated by a few hundred micrometers to balance their interaction and competition. However, it has been challenging to define a microscale spatial microbial structure in miniature biobatteries. Here, an innovative technique to design microscale spatial structures with microbial multispecies for significant improvement of the biobattery performance is demonstrated. A solid‐state layer‐by‐layer agar‐based culture platform is proposed, where individual microcolonies separately confined in microscale agar layers form a 3‐D spatial structure allowing for the exchange of metabolites without physical contact between the individual species. The optimized microbial co‐cultures are determined from selected hypothesis‐driven naturally‐occurring bacteria. Vertically and horizontally structured 3‐D microbial communities in solid‐state agar‐based microcompartments demonstrate the practicability of the biobattery, generating longer and greater power in a more self‐sustaining manner than monocultures and other mixed populations.
more » « less- Award ID(s):
- 1920979
- NSF-PAR ID:
- 10387615
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Energy Materials
- Volume:
- 11
- Issue:
- 22
- ISSN:
- 1614-6832
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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